Start by brewing strong coffee and pour it into a shallow dish; stir in almond extract and rum if using, then set it aside to cool.
Carefully separate the egg whites and yolks into two different bowls.
Whip the egg whites with half the sugar until stiff peaks form, then transfer them gently to a clean large bowl.
Beat the egg yolks with the remaining sugar until pale and fluffy, mix in the mascarpone until smooth.
Blend the pistachio paste, vanilla extract, and almond extract into the mascarpone and yolk mixture.
Fold half of the mascarpone mixture into the whipped egg whites gently, then fold in the rest until fully combined without deflating the mixture.
Quickly dip each lady finger into the coffee mixture on both sides and arrange a single layer in a 9x9 inch pan.
Spread half of the mascarpone cream over the lady fingers evenly.
Add another layer of quickly dipped lady fingers, then top with the remaining mascarpone cream.
Sprinkle the finely chopped pistachios on top for garnish.
Cover and refrigerate the tiramisu for at least 4 hours or overnight to allow the flavors to meld before serving.